Employee Benefit Plans (Tables)

9 Months Ended

Sep. 30, 2011

Employee Benefit Plans [Abstract]

Consolidated Net Periodic Benefit Costs

	Three Months  Ended September 30, 2010						Three Months  Ended September 30, 2011
	Pension Benefits			Other  Post- Retirement Benefits			Pension Benefits			Other  Post- Retirement Benefits
Components of net periodic benefit costs:
Service cost	$	1,687		$	63		$	3,251		$	141
Interest cost	840			338			1,358			230
Expected return on plan assets	(890		)	—			(1,225		)	—
Amortization of prior service cost (credit)	76			(213		)	76			(212		)
Amortization of actuarial loss	138			100			766			1
Settlement cost	—			—			70			—
Net periodic benefit cost	$	1,851		$	288		$	4,296		$	160

	Nine Months  Ended September 30, 2010						Nine Months  Ended September 30, 2011
	Pension Benefits			Other  Post- Retirement Benefits			Pension Benefits			Other  Post- Retirement Benefits
Components of net periodic benefit costs:
Service cost	$	5,040		$	239		$	7,221		$	323
Interest cost	2,506			744			3,257			749
Expected return on plan assets	(2,664		)	—			(3,268		)	—
Amortization of prior service cost (credit)	230			(638		)	230			(638		)
Amortization of actuarial loss	388			100			1,068			126
Settlement cost	—			—			70			—
Net periodic benefit cost	$	5,500		$	445		$	8,578		$	560